Event
Qualcomm Microsystems Seminar: Thomas Kenney, "Building Devices and Packages with MEMS"
Friday, May 10, 2013
4:00 p.m.
1146 A.V. Williams Building
Ian White
ianwhite@umd.edu
Qualcomm Microsystems Seminar Series
Using MEMS to Build Devices and Packages at the Same Time
| video |
Thomas Kenney
Stanford University
Abstract
MEMS Resonators have been studied for almost 50 years, with a continuous interest in their use as frequency references. Unfortunately, the promise of MEMS resonators for these applications has always been limited by observations of drift in frequency, which has been attributed to various mechanisms, such as fatigue and creep, and other intrinsic phenomena. Until recently, the lack of frequency stability has prevented the use of MEMS for time references.
Our group has worked in collaboration with Bosch to develop a wafer-scale MEMS encapsulation process that has enabled a solution to many of the problems with MEMS resonators. This presentation will discuss the encapsulation process, and the opportunities for implementation of temperature compensation and control. The encapsulation process is inherently clean, and directly enables long-term stability. SiTime is presently commercializing this technology, and there is reason to believe that MEMS will replace Quartz crystal resonators for electronics timing. More recently, we have been leveraging this process for pressure sensors, accelerometers, gyroscopes, thermometers, and other MEMS devices. The ability to co-fabricate all of this in a process that delivers high yield and is consistent with volume manufacturing has us thinking about multi-sensor chips and many other applications.
Biography
Thomas W. Kenny received the B.S. degree in physics from the University of Minnesota, in 1983, and the M.S. and Ph.D. degrees in physics from the University of California, Berkeley, in 1987 and 1989, respectively. From 1989 to 1993, he was with the Jet Propulsion Laboratory, where his research focused on the development of high- resolution microsensors. In 1994, he joined the Department of Mechanical Engineering, Stanford Universitym where he directs microsensor-based research on resonators, wafer-scale packaging, cantilever beam force sensors, microfluidics, and novel fabrication techniques for micro- mechanical structures. He was Founder and CTO of Cooligy, Sunnyvale, CA, a microfluidics chip cooling component manufacturer, and Founder and a Board Member of SiTime Corporation, a developer of CMOS timing references using MEMS resonators. He is currently a Stanford Bosch Faculty Development Scholar and was the General Chairman of the 2006 Hilton Head Solid State Sensor, Actuator, and Microsystems Workshop. From October 2006 through September 2010, he was on leave to serve as Program Manager in the Microsystems Technology Office at the Defense Advanced Research Projects Agency, starting and managing programs in thermal management, nanomanufacturing, manipulation of Casimir forces, and the Young Faculty Award. He has authored or coauthored over 250 scientific papers and is a holder of 48 issued patents.
Kenny's group is researching fundamental issues and applications of micromechanical structures. These devices are usually fabricated from silicon wafers using integrated circuit fabrication tools. Using these techniques, the group builds sensitive accelerometers, infrared detectors, and force-sensing cantilevers. This research has many applications, including integrated packaging, inertial navigation, fundamental force measurements, experiments on bio-molecules, device cooling, bio-analytical instruments, and small robots. Because this research field is multidisciplinary in nature, work in this group is characterized by strong collaborations with other departments, as well as with local industry.
